Náttúrufræðingurinn - 1993, Page 38

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SUMMARY
Late ice age changes at
Kvíárjökull glacier
by
Sigurður Björnsson
Kvísker
Austur-Skaftafellssýsla
1S-785 FAGURHÓLSMÝRl
Iceland
The major part of the article deals with the
changes in the landforms in the vicinity of the
Kvíárjökull glacier, and the reasons for these
changes. The landscape there exhibits some
rather unusual features. Surrounding the
glacier are some of the largest lateral and
terminal morains described. The glacier lies
in a very deep channel when compared to its
present volume and is flanked by very steep
mountainsides. There have been marked
changes in the glacier itself in historical time.
Young volcanics are found high up on the
mountains on both sides of Kvíárjökull, both
lava and tephra, which the glacier has either
not overridden or only partially so. These
volcanic products are not traceable to any
nearby craters or vents and, indeed, there are
none such recognizable in the immediate
vicinity. The landforms and the types and
distribution of the volcanic products show
indisputably that they originated in craters and
vents that were high up on mountains, where
now the deep bed of the valley glacier is to be
found.
There are flood deposits from a glacial burst
(jökulhlaup) on the lowland on each side of
Kvíáijökull, which indicate a large flood there
early in postglacial time. The deposits seem
to have been transported through ravines
alongside the mountains on either side of the
present Kvíárjökull. There seems to have been
a large obstruction that forced the floods to
flow east and west of the mountains where
the glacier now lies.
These observations are interpreted as
follows: The mountains that now abut the
Kvíárjökull were formerly flanks of a large
volcanic cone. At the end of the Ice Age, the
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